Yes, this was supposed to be The Spanish Cape Mystery (1935) by Ellery Queen in preparation for the forthcoming spoiler-filled look at Halfway House (1936). Yes, you all warned me that book was awful, and you were correct. Let’s instead board a cruise ship stuffed with munitions at the outset of the Second World War and watch the eight — or is it nine? — passengers slowly get to know each other until one of them is found murdered in their cabin, the corpse peppered with fingerprints which do not match those of anyone on board. Aaah, I feel better already — man, I love the work of John Dickson Carr; the idea of having never discovered it makes me feel a little unwell.